Lamp shade



. Jan. 6, 1942. D J Ross A 2,269,128

LAMP SHADE 'Filed Dec. 1s, 1959 Illllllllllllllllllllll\\\\\\\\\\\m\ IN VENTOR.

' ATTORNEY'.

Patented Jan. 6, 1942 UNITED STATES yPATENT LOF FICE y @LAMP .sHADE VDavid J. Ross, `Benton Harbor, Mich. Application vDecember 13, 1939, serial No. 309,077

y(o1. v.24o-108) Claims.

This .invention relatesl to improvements .in lamp shades Thisinvention relates to lamp shades and the method of producing them. It has .for its objects:

First, the .production of a new and improved lampv shade.

Second, the production of .such a lamp shade in Whichsheet cellulose acetate or the like is'employed.

y Third, to producesuch a lampshad'e in which the-celluloseacetate or the like is pleated.

Fourth, to produce such a lamp shade in which the cellulose acetate forming the walls' of the shade is bowed inwardly to give a graceful and beautiful appearance to the shade.

Fifth, to produce such a shade in which it is not necessary to employ stays or connecting- Wires between the top and bottom rings in order to hold the rings together or to give the desired form to the walls of the shade.

Sixth, to producesuch a lamp shade which maybe made simply and economically.

Seventh, to` produce such a lamp shade having a decorative skirt which may be easily applied tothe shade and retained in position.

Eighth, to produce a new and improved method of ,producing lamp shades of pleated sheetcellulose acetate.

Ninth, to produce such a method whichgives to the lamp shade a pleasing and graceful shape.

Tenth, to produce such a method in which the walls of the lamp shade are bowed inwardly on graceful lines. l

Eleventh, to provide such a method whichmay be carried out economically and simply.

Twelfth, to produce a new and improved method of applying a decorative skirttoalamp shade made of cellulose acetate or the like.

Further objects and advantagespertaining `to details and'economies of construction vand opera,- tion will appear from the v.description to follow. Preferred embodiments of my invention appear in the accompanying drawing, in which:

Fig. 1 is a plan view of a sheet of cellulose acetate used in practicing my invention.

Fig. 2 is a perspective View of a tube formed of pleated sheet cellulose acetate or the like used in practicing my invention.

Fig. 3 is a detail sectional view through a lamp shade in the process of construction in accordance with my invention, showing the form used to expand the .tube shown in Fig. 2.

Fig. 4 is a detail view showing a portion of the wall of a tube employed in carrying out my invention.

Fig. 5 is a detail view of the same portion of the material shown in Fig. 4 expanded and held in position to receive the rings at the top and the bottom to produce the finished lamp shade.

Fig. 6 is -a detail sectional View through a iinished lamp shade made in accordance with my invention.

Fig. 7 is a view showing a skirt applied to a lamp shade such as is shown in Fig. 6.

Fig. 8 is a detail view taken on line y8-'8 of Fig. 7 showing the manner of application ofthe skirt.

Incarryingsout my invention, I make use of a .strip I of sheet .cellulose acetate or the like having'pleats 2 'extending transversely of .said strip. The strip I isiformed into a tube 3 asindicated rin Fig. `2. The edges vare cemented or otherwise fastened together.

. The `pleated sheet cellulose-acetate is a resilient material in thatif it is stretched out .by eX- panding 'the pleats, a tension is set up tending to close up thepleats.

In the tube 3, I insert a frusto-conical sheet metal Aform 4 which has across bar V5 therein to facilitate handling. 'Ihe altitude of the frusto-conical form 4 is less than the length of the tube l3 and I position the form so as to leave the edges of .the material forming the ends of .the tube easy of access. ameter that it expands the pleats 2 at bothends vof the .tube 3. 1

In Fig. 4, I show a cross sectional view of 4the pleats in the'tube 3 prior-t0 `the insertionof the form. 'In Fig. 5, I -show the pleats afterthe insertion of the form. It should benoted that the pleats at both the .top and bottom areexpanded somewhat.

While the .pleats are held in expanded lposition bythe form 4, I fasten to the edges of :the material at the ends of the tube rings 6 whichare made of sheet Ymetal and are .provided with grooves 1 into which the .edges .of the .material of the tube are inserted. After this step the rings are clamped as shownl in Fig. 6 to hold the material in expanded form. The upper ring 6 may be provided with a cross bar 8 to which is fastened a wire lamp bulb clamping device shown at 9. y

After the rings 6 have been clamped in place, the form 4 is removed. The side walls of the lamp shade assume the graceful inwardly bowed curve shown in Fig. 6.

I believe that this form is assumed because The form 4 is of suchdiof internal tension in the material. The pleats at the ends of the tube 3 are expanded and the rings B hold them thus expanded. The expansion of the material tends to create a tension tending to close up the pleats 2 and this tension causes the side walls of the shade to assume this form and in the finished shade the material is under tension.

I have found that the degree of bow in the walls of the shade may be determined either by the number of pleats or by the thickness of the material. If there are a small number of pleats, there is a greater tension in the shade so that the walls bow inwardly to a greater extent than in a shade with more pleats.` If the material is very thin, there is a greater tendency to bow, sincerthicker material is stiffer and resists the tension tending to shape the shade. I have found that for small shades of four inches in height, very satisfactory results can be obtained using cellulose acetate or the like three-thousandths of an inch thick. For taller shades, it would be possible to use slightly thicker material.

I have found that in the above mentioned shades very desirable results are obtained when the material is so pleated that its length is reduced to one-third that of the unpleated material. I prefer to use material in which there are sixteen pleats to the inch in such shades, although, of couse, there can be variations of these factors.

A highly decorative skirt may be applied to the lamp shade above described. I have found that such a skirt can be produced by running one edge of a strip I of pleated cellulose acetate or the like having transverse pleats over a heated roller which expands the pleats at said edge and iixes them in expanded form to elongate the edge and give a rullied effect as indicated at I I in Fig. '7.

The application of the skirt is greatly simplified if the strip is scored longitudinally as indicated at I2 between its edges. The elongation above referred to sets up-a tension in the strip Ill which tends to distort the untreated edge I3 and the scoring at I2 breaks the strip suiciently so that the tension created by treating the edge of the strip to ruffle it does not distort the edge I3 of the strip. This edge will lie flat when a ring formed of the strip Ill is applied to the lamp shade with the pleats of the edge I3 in register with the pleats of the shade. When the skirt has been arranged at the desired position, it may be cemented as at I4, either by using a suitable cement or a suitable solvent for the cellulose acetate or the like which will soften it and permit adhesion.

It will be apparent that my shade can be made easily and simply and that the shade has a desirable graceful form whichis acquired without use of any stays or wires to interfere with illumination or mar the beauty of the shade when it is in use.

The terms and expressions which have been employed here are used as terms of description and not as terms of limitation. There is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof. It is recognized that various modifications are possible within the scope of the invention claimed.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A lamp shade comprising a pair of grooved rings connected by and clamping the edges of pleated sheet cellulose acetate having its pleats extending between said rings, the pleats in the material at the rings being expanded beyond the normal position and size they would assume if unrestricted to put the material under tension tending to close upthe pleats and the material between the rings being bowed inwardly by tension in the pleated material tending to close up the pleats.

2. A lamp shade comprising a pair of rings connected by and holding the edges of pleated sheet cellulose acetate having its pleats extending between said rings, the pleats in the material at the rings being expanded beyond the normal position and size they would assume if unrestricted to put the material under tension tending to close up the pleats and the material between the rings being bowed inwardly by tension in the pleated material tending to close up the pleats.

3. A lamp shade comprising a pair of grooved rings connected by and clamping the edges of pleated sheet cellulose acetate having its pleats extending between said rings, the pleats in the material at one of the rings being expanded beyond the normal position and size they would assume if unrestricted to put the material under tension tending to close up the pleats and the material between the rings being bowed inwardly by tension in the pleated material tending to close up the pleats.

4.A lamp shade comprising a pair of rings connected by and holding the edges of pleated sheet cellulose acetate having its pleats extending between said rings, the pleats in the material at one of the rings being expanded beyond the normal position and size they would assume if unrestricted to put the material under tension tending to close up the pleats and the material between the rings being bowed inwardly by tension in the pleated material tending to close up the pleats. i

5. A lamp shade comprising a body portion of pleated cellulose acetate, and a skirt thereon comprising a strip of said cellulose acetate or the like having transverse pleats, the pleats at one edge of said strip being in register with the pleats of the body of the lamp shade and at the other edge fixed in relatively expanded position whereby a ruffled eect is produced, and a line of scoring extending between and parallel to said edges of said strip and breaking the pleats.

DAVID J. ROSS. 

